/***
 * ASM: a very small and fast Java bytecode manipulation framework
 * Copyright (c) 2000-2005 INRIA, France Telecom
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. Neither the name of the copyright holders nor the names of its
 *    contributors may be used to endorse or promote products derived from
 *    this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF
 * THE POSSIBILITY OF SUCH DAMAGE.
 */
package clojure.asm;

/**
 * A {@link ClassVisitor} that generates classes in bytecode form. More
 * precisely this visitor generates a byte array conforming to the Java class
 * file format. It can be used alone, to generate a Java class "from scratch",
 * or with one or more {@link ClassReader ClassReader} and adapter class visitor
 * to generate a modified class from one or more existing Java classes.
 *
 * @author Eric Bruneton
 */
public class ClassWriter implements ClassVisitor{

/**
 * Flag to automatically compute the maximum stack size and the maximum
 * number of local variables of methods. If this flag is set, then the
 * arguments of the {@link MethodVisitor#visitMaxs visitMaxs} method of the
 * {@link MethodVisitor} returned by the {@link #visitMethod visitMethod}
 * method will be ignored, and computed automatically from the signature and
 * the bytecode of each method.
 *
 * @see #ClassWriter(int)
 */
public final static int COMPUTE_MAXS = 1;

/**
 * Flag to automatically compute the stack map frames of methods from
 * scratch. If this flag is set, then the calls to the
 * {@link MethodVisitor#visitFrame} method are ignored, and the stack map
 * frames are recomputed from the methods bytecode. The arguments of the
 * {@link MethodVisitor#visitMaxs visitMaxs} method are also ignored and
 * recomputed from the bytecode. In other words, computeFrames implies
 * computeMaxs.
 *
 * @see #ClassWriter(int)
 */
public final static int COMPUTE_FRAMES = 2;

/**
 * The type of instructions without any argument.
 */
final static int NOARG_INSN = 0;

/**
 * The type of instructions with an signed byte argument.
 */
final static int SBYTE_INSN = 1;

/**
 * The type of instructions with an signed short argument.
 */
final static int SHORT_INSN = 2;

/**
 * The type of instructions with a local variable index argument.
 */
final static int VAR_INSN = 3;

/**
 * The type of instructions with an implicit local variable index argument.
 */
final static int IMPLVAR_INSN = 4;

/**
 * The type of instructions with a type descriptor argument.
 */
final static int TYPE_INSN = 5;

/**
 * The type of field and method invocations instructions.
 */
final static int FIELDORMETH_INSN = 6;

/**
 * The type of the INVOKEINTERFACE instruction.
 */
final static int ITFMETH_INSN = 7;

/**
 * The type of instructions with a 2 bytes bytecode offset label.
 */
final static int LABEL_INSN = 8;

/**
 * The type of instructions with a 4 bytes bytecode offset label.
 */
final static int LABELW_INSN = 9;

/**
 * The type of the LDC instruction.
 */
final static int LDC_INSN = 10;

/**
 * The type of the LDC_W and LDC2_W instructions.
 */
final static int LDCW_INSN = 11;

/**
 * The type of the IINC instruction.
 */
final static int IINC_INSN = 12;

/**
 * The type of the TABLESWITCH instruction.
 */
final static int TABL_INSN = 13;

/**
 * The type of the LOOKUPSWITCH instruction.
 */
final static int LOOK_INSN = 14;

/**
 * The type of the MULTIANEWARRAY instruction.
 */
final static int MANA_INSN = 15;

/**
 * The type of the WIDE instruction.
 */
final static int WIDE_INSN = 16;

/**
 * The instruction types of all JVM opcodes.
 */
static byte[] TYPE;

/**
 * The type of CONSTANT_Class constant pool items.
 */
final static int CLASS = 7;

/**
 * The type of CONSTANT_Fieldref constant pool items.
 */
final static int FIELD = 9;

/**
 * The type of CONSTANT_Methodref constant pool items.
 */
final static int METH = 10;

/**
 * The type of CONSTANT_InterfaceMethodref constant pool items.
 */
final static int IMETH = 11;

/**
 * The type of CONSTANT_String constant pool items.
 */
final static int STR = 8;

/**
 * The type of CONSTANT_Integer constant pool items.
 */
final static int INT = 3;

/**
 * The type of CONSTANT_Float constant pool items.
 */
final static int FLOAT = 4;

/**
 * The type of CONSTANT_Long constant pool items.
 */
final static int LONG = 5;

/**
 * The type of CONSTANT_Double constant pool items.
 */
final static int DOUBLE = 6;

/**
 * The type of CONSTANT_NameAndType constant pool items.
 */
final static int NAME_TYPE = 12;

/**
 * The type of CONSTANT_Utf8 constant pool items.
 */
final static int UTF8 = 1;

/**
 * Normal type Item stored in the ClassWriter {@link ClassWriter#typeTable},
 * instead of the constant pool, in order to avoid clashes with normal
 * constant pool items in the ClassWriter constant pool's hash table.
 */
final static int TYPE_NORMAL = 13;

/**
 * Uninitialized type Item stored in the ClassWriter
 * {@link ClassWriter#typeTable}, instead of the constant pool, in order to
 * avoid clashes with normal constant pool items in the ClassWriter constant
 * pool's hash table.
 */
final static int TYPE_UNINIT = 14;

/**
 * Merged type Item stored in the ClassWriter {@link ClassWriter#typeTable},
 * instead of the constant pool, in order to avoid clashes with normal
 * constant pool items in the ClassWriter constant pool's hash table.
 */
final static int TYPE_MERGED = 15;

/**
 * The class reader from which this class writer was constructed, if any.
 */
ClassReader cr;

/**
 * Minor and major version numbers of the class to be generated.
 */
int version;

/**
 * Index of the next item to be added in the constant pool.
 */
int index;

/**
 * The constant pool of this class.
 */
ByteVector pool;

/**
 * The constant pool's hash table data.
 */
Item[] items;

/**
 * The threshold of the constant pool's hash table.
 */
int threshold;

/**
 * A reusable key used to look for items in the {@link #items} hash table.
 */
Item key;

/**
 * A reusable key used to look for items in the {@link #items} hash table.
 */
Item key2;

/**
 * A reusable key used to look for items in the {@link #items} hash table.
 */
Item key3;

/**
 * A type table used to temporarily store internal names that will not
 * necessarily be stored in the constant pool. This type table is used by
 * the control flow and data flow analysis algorithm used to compute stack
 * map frames from scratch. This array associates to each index <tt>i</tt>
 * the Item whose index is <tt>i</tt>. All Item objects stored in this
 * array are also stored in the {@link #items} hash table. These two arrays
 * allow to retrieve an Item from its index or, conversly, to get the index
 * of an Item from its value. Each Item stores an internal name in its
 * {@link Item#strVal1} field.
 */
Item[] typeTable;

/**
 * Number of elements in the {@link #typeTable} array.
 */
private short typeCount; // TODO int?

/**
 * The access flags of this class.
 */
private int access;

/**
 * The constant pool item that contains the internal name of this class.
 */
private int name;

/**
 * The internal name of this class.
 */
String thisName;

/**
 * The constant pool item that contains the signature of this class.
 */
private int signature;

/**
 * The constant pool item that contains the internal name of the super class
 * of this class.
 */
private int superName;

/**
 * Number of interfaces implemented or extended by this class or interface.
 */
private int interfaceCount;

/**
 * The interfaces implemented or extended by this class or interface. More
 * precisely, this array contains the indexes of the constant pool items
 * that contain the internal names of these interfaces.
 */
private int[] interfaces;

/**
 * The index of the constant pool item that contains the name of the source
 * file from which this class was compiled.
 */
private int sourceFile;

/**
 * The SourceDebug attribute of this class.
 */
private ByteVector sourceDebug;

/**
 * The constant pool item that contains the name of the enclosing class of
 * this class.
 */
private int enclosingMethodOwner;

/**
 * The constant pool item that contains the name and descriptor of the
 * enclosing method of this class.
 */
private int enclosingMethod;

/**
 * The runtime visible annotations of this class.
 */
private AnnotationWriter anns;

/**
 * The runtime invisible annotations of this class.
 */
private AnnotationWriter ianns;

/**
 * The non standard attributes of this class.
 */
private Attribute attrs;

/**
 * The number of entries in the InnerClasses attribute.
 */
private int innerClassesCount;

/**
 * The InnerClasses attribute.
 */
private ByteVector innerClasses;

/**
 * The fields of this class. These fields are stored in a linked list of
 * {@link FieldWriter} objects, linked to each other by their
 * {@link FieldWriter#next} field. This field stores the first element of
 * this list.
 */
FieldWriter firstField;

/**
 * The fields of this class. These fields are stored in a linked list of
 * {@link FieldWriter} objects, linked to each other by their
 * {@link FieldWriter#next} field. This field stores the last element of
 * this list.
 */
FieldWriter lastField;

/**
 * The methods of this class. These methods are stored in a linked list of
 * {@link MethodWriter} objects, linked to each other by their
 * {@link MethodWriter#next} field. This field stores the first element of
 * this list.
 */
MethodWriter firstMethod;

/**
 * The methods of this class. These methods are stored in a linked list of
 * {@link MethodWriter} objects, linked to each other by their
 * {@link MethodWriter#next} field. This field stores the last element of
 * this list.
 */
MethodWriter lastMethod;

/**
 * <tt>true</tt> if the maximum stack size and number of local variables
 * must be automatically computed.
 */
private boolean computeMaxs;

/**
 * <tt>true</tt> if the stack map frames must be recomputed from scratch.
 */
private boolean computeFrames;

/**
 * <tt>true</tt> if the stack map tables of this class are invalid. The
 * {@link MethodWriter#resizeInstructions} method cannot transform existing
 * stack map tables, and so produces potentially invalid classes when it is
 * executed. In this case the class is reread and rewritten with the
 * {@link #COMPUTE_FRAMES} option (the resizeInstructions method can resize
 * stack map tables when this option is used).
 */
boolean invalidFrames;

// ------------------------------------------------------------------------
// Static initializer
// ------------------------------------------------------------------------

/**
 * Computes the instruction types of JVM opcodes.
 */
static
	{
	int i;
	byte[] b = new byte[220];
	String s = "AAAAAAAAAAAAAAAABCKLLDDDDDEEEEEEEEEEEEEEEEEEEEAAAAAAAADD"
	           + "DDDEEEEEEEEEEEEEEEEEEEEAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA"
	           + "AAAAAAAAAAAAAAAAAMAAAAAAAAAAAAAAAAAAAAIIIIIIIIIIIIIIIIDNOAA"
	           + "AAAAGGGGGGGHAFBFAAFFAAQPIIJJIIIIIIIIIIIIIIIIII";
	for(i = 0; i < b.length; ++i)
		{
		b[i] = (byte) (s.charAt(i) - 'A');
		}
	TYPE = b;

	// code to generate the above string
	//
	// // SBYTE_INSN instructions
	// b[Constants.NEWARRAY] = SBYTE_INSN;
	// b[Constants.BIPUSH] = SBYTE_INSN;
	//
	// // SHORT_INSN instructions
	// b[Constants.SIPUSH] = SHORT_INSN;
	//
	// // (IMPL)VAR_INSN instructions
	// b[Constants.RET] = VAR_INSN;
	// for (i = Constants.ILOAD; i <= Constants.ALOAD; ++i) {
	// b[i] = VAR_INSN;
	// }
	// for (i = Constants.ISTORE; i <= Constants.ASTORE; ++i) {
	// b[i] = VAR_INSN;
	// }
	// for (i = 26; i <= 45; ++i) { // ILOAD_0 to ALOAD_3
	// b[i] = IMPLVAR_INSN;
	// }
	// for (i = 59; i <= 78; ++i) { // ISTORE_0 to ASTORE_3
	// b[i] = IMPLVAR_INSN;
	// }
	//
	// // TYPE_INSN instructions
	// b[Constants.NEW] = TYPE_INSN;
	// b[Constants.ANEWARRAY] = TYPE_INSN;
	// b[Constants.CHECKCAST] = TYPE_INSN;
	// b[Constants.INSTANCEOF] = TYPE_INSN;
	//
	// // (Set)FIELDORMETH_INSN instructions
	// for (i = Constants.GETSTATIC; i <= Constants.INVOKESTATIC; ++i) {
	// b[i] = FIELDORMETH_INSN;
	// }
	// b[Constants.INVOKEINTERFACE] = ITFMETH_INSN;
	//
	// // LABEL(W)_INSN instructions
	// for (i = Constants.IFEQ; i <= Constants.JSR; ++i) {
	// b[i] = LABEL_INSN;
	// }
	// b[Constants.IFNULL] = LABEL_INSN;
	// b[Constants.IFNONNULL] = LABEL_INSN;
	// b[200] = LABELW_INSN; // GOTO_W
	// b[201] = LABELW_INSN; // JSR_W
	// // temporary opcodes used internally by ASM - see Label and
	// MethodWriter
	// for (i = 202; i < 220; ++i) {
	// b[i] = LABEL_INSN;
	// }
	//
	// // LDC(_W) instructions
	// b[Constants.LDC] = LDC_INSN;
	// b[19] = LDCW_INSN; // LDC_W
	// b[20] = LDCW_INSN; // LDC2_W
	//
	// // special instructions
	// b[Constants.IINC] = IINC_INSN;
	// b[Constants.TABLESWITCH] = TABL_INSN;
	// b[Constants.LOOKUPSWITCH] = LOOK_INSN;
	// b[Constants.MULTIANEWARRAY] = MANA_INSN;
	// b[196] = WIDE_INSN; // WIDE
	//
	// for (i = 0; i < b.length; ++i) {
	// System.err.print((char)('A' + b[i]));
	// }
	// System.err.println();
	}

// ------------------------------------------------------------------------
// Constructor
// ------------------------------------------------------------------------

/**
 * Constructs a new {@link ClassWriter} object.
 *
 * @param flags option flags that can be used to modify the default behavior
 *              of this class. See {@link #COMPUTE_MAXS}, {@link #COMPUTE_FRAMES}.
 */
public ClassWriter(final int flags){
	index = 1;
	pool = new ByteVector();
	items = new Item[256];
	threshold = (int) (0.75d * items.length);
	key = new Item();
	key2 = new Item();
	key3 = new Item();
	this.computeMaxs = (flags & COMPUTE_MAXS) != 0;
	this.computeFrames = (flags & COMPUTE_FRAMES) != 0;
}

/**
 * Constructs a new {@link ClassWriter} object and enables optimizations for
 * "mostly add" bytecode transformations. These optimizations are the
 * following:
 * <p/>
 * <ul> <li>The constant pool from the original class is copied as is in
 * the new class, which saves time. New constant pool entries will be added
 * at the end if necessary, but unused constant pool entries <i>won't be
 * removed</i>.</li> <li>Methods that are not transformed are copied as
 * is in the new class, directly from the original class bytecode (i.e.
 * without emitting visit events for all the method instructions), which
 * saves a <i>lot</i> of time. Untransformed methods are detected by the
 * fact that the {@link ClassReader} receives {@link MethodVisitor} objects
 * that come from a {@link ClassWriter} (and not from a custom
 * {@link ClassAdapter} or any other {@link ClassVisitor} instance).</li>
 * </ul>
 *
 * @param classReader the {@link ClassReader} used to read the original
 *                    class. It will be used to copy the entire constant pool from the
 *                    original class and also to copy other fragments of original
 *                    bytecode where applicable.
 * @param flags       option flags that can be used to modify the default behavior
 *                    of this class. See {@link #COMPUTE_MAXS}, {@link #COMPUTE_FRAMES}.
 */
public ClassWriter(final ClassReader classReader, final int flags){
	this(flags);
	classReader.copyPool(this);
	this.cr = classReader;
}

// ------------------------------------------------------------------------
// Implementation of the ClassVisitor interface
// ------------------------------------------------------------------------

public void visit(
		final int version,
		final int access,
		final String name,
		final String signature,
		final String superName,
		final String[] interfaces){
	this.version = version;
	this.access = access;
	this.name = newClass(name);
	thisName = name;
	if(signature != null)
		{
		this.signature = newUTF8(signature);
		}
	this.superName = superName == null ? 0 : newClass(superName);
	if(interfaces != null && interfaces.length > 0)
		{
		interfaceCount = interfaces.length;
		this.interfaces = new int[interfaceCount];
		for(int i = 0; i < interfaceCount; ++i)
			{
			this.interfaces[i] = newClass(interfaces[i]);
			}
		}
}

public void visitSource(final String file, final String debug){
	if(file != null)
		{
		sourceFile = newUTF8(file);
		}
	if(debug != null)
		{
		sourceDebug = new ByteVector().putUTF8(debug);
		}
}

public void visitOuterClass(
		final String owner,
		final String name,
		final String desc){
	enclosingMethodOwner = newClass(owner);
	if(name != null && desc != null)
		{
		enclosingMethod = newNameType(name, desc);
		}
}

public AnnotationVisitor visitAnnotation(
		final String desc,
		final boolean visible){
	ByteVector bv = new ByteVector();
	// write type, and reserve space for values count
	bv.putShort(newUTF8(desc)).putShort(0);
	AnnotationWriter aw = new AnnotationWriter(this, true, bv, bv, 2);
	if(visible)
		{
		aw.next = anns;
		anns = aw;
		}
	else
		{
		aw.next = ianns;
		ianns = aw;
		}
	return aw;
}

public void visitAttribute(final Attribute attr){
	attr.next = attrs;
	attrs = attr;
}

public void visitInnerClass(
		final String name,
		final String outerName,
		final String innerName,
		final int access){
	if(innerClasses == null)
		{
		innerClasses = new ByteVector();
		}
	++innerClassesCount;
	innerClasses.putShort(name == null ? 0 : newClass(name));
	innerClasses.putShort(outerName == null ? 0 : newClass(outerName));
	innerClasses.putShort(innerName == null ? 0 : newUTF8(innerName));
	innerClasses.putShort(access);
}

public FieldVisitor visitField(
		final int access,
		final String name,
		final String desc,
		final String signature,
		final Object value){
	return new FieldWriter(this, access, name, desc, signature, value);
}

public MethodVisitor visitMethod(
		final int access,
		final String name,
		final String desc,
		final String signature,
		final String[] exceptions){
	return new MethodWriter(this,
	                        access,
	                        name,
	                        desc,
	                        signature,
	                        exceptions,
	                        computeMaxs,
	                        computeFrames);
}

public void visitEnd(){
}

// ------------------------------------------------------------------------
// Other public methods
// ------------------------------------------------------------------------

/**
 * Returns the bytecode of the class that was build with this class writer.
 *
 * @return the bytecode of the class that was build with this class writer.
 */
public byte[] toByteArray(){
	// computes the real size of the bytecode of this class
	int size = 24 + 2 * interfaceCount;
	int nbFields = 0;
	FieldWriter fb = firstField;
	while(fb != null)
		{
		++nbFields;
		size += fb.getSize();
		fb = fb.next;
		}
	int nbMethods = 0;
	MethodWriter mb = firstMethod;
	while(mb != null)
		{
		++nbMethods;
		size += mb.getSize();
		mb = mb.next;
		}
	int attributeCount = 0;
	if(signature != 0)
		{
		++attributeCount;
		size += 8;
		newUTF8("Signature");
		}
	if(sourceFile != 0)
		{
		++attributeCount;
		size += 8;
		newUTF8("SourceFile");
		}
	if(sourceDebug != null)
		{
		++attributeCount;
		size += sourceDebug.length + 4;
		newUTF8("SourceDebugExtension");
		}
	if(enclosingMethodOwner != 0)
		{
		++attributeCount;
		size += 10;
		newUTF8("EnclosingMethod");
		}
	if((access & Opcodes.ACC_DEPRECATED) != 0)
		{
		++attributeCount;
		size += 6;
		newUTF8("Deprecated");
		}
	if((access & Opcodes.ACC_SYNTHETIC) != 0
	   && (version & 0xffff) < Opcodes.V1_5)
		{
		++attributeCount;
		size += 6;
		newUTF8("Synthetic");
		}
	if(innerClasses != null)
		{
		++attributeCount;
		size += 8 + innerClasses.length;
		newUTF8("InnerClasses");
		}
	if(anns != null)
		{
		++attributeCount;
		size += 8 + anns.getSize();
		newUTF8("RuntimeVisibleAnnotations");
		}
	if(ianns != null)
		{
		++attributeCount;
		size += 8 + ianns.getSize();
		newUTF8("RuntimeInvisibleAnnotations");
		}
	if(attrs != null)
		{
		attributeCount += attrs.getCount();
		size += attrs.getSize(this, null, 0, -1, -1);
		}
	size += pool.length;
	// allocates a byte vector of this size, in order to avoid unnecessary
	// arraycopy operations in the ByteVector.enlarge() method
	ByteVector out = new ByteVector(size);
	out.putInt(0xCAFEBABE).putInt(version);
	out.putShort(index).putByteArray(pool.data, 0, pool.length);
	out.putShort(access).putShort(name).putShort(superName);
	out.putShort(interfaceCount);
	for(int i = 0; i < interfaceCount; ++i)
		{
		out.putShort(interfaces[i]);
		}
	out.putShort(nbFields);
	fb = firstField;
	while(fb != null)
		{
		fb.put(out);
		fb = fb.next;
		}
	out.putShort(nbMethods);
	mb = firstMethod;
	while(mb != null)
		{
		mb.put(out);
		mb = mb.next;
		}
	out.putShort(attributeCount);
	if(signature != 0)
		{
		out.putShort(newUTF8("Signature")).putInt(2).putShort(signature);
		}
	if(sourceFile != 0)
		{
		out.putShort(newUTF8("SourceFile")).putInt(2).putShort(sourceFile);
		}
	if(sourceDebug != null)
		{
		int len = sourceDebug.length - 2;
		out.putShort(newUTF8("SourceDebugExtension")).putInt(len);
		out.putByteArray(sourceDebug.data, 2, len);
		}
	if(enclosingMethodOwner != 0)
		{
		out.putShort(newUTF8("EnclosingMethod")).putInt(4);
		out.putShort(enclosingMethodOwner).putShort(enclosingMethod);
		}
	if((access & Opcodes.ACC_DEPRECATED) != 0)
		{
		out.putShort(newUTF8("Deprecated")).putInt(0);
		}
	if((access & Opcodes.ACC_SYNTHETIC) != 0
	   && (version & 0xffff) < Opcodes.V1_5)
		{
		out.putShort(newUTF8("Synthetic")).putInt(0);
		}
	if(innerClasses != null)
		{
		out.putShort(newUTF8("InnerClasses"));
		out.putInt(innerClasses.length + 2).putShort(innerClassesCount);
		out.putByteArray(innerClasses.data, 0, innerClasses.length);
		}
	if(anns != null)
		{
		out.putShort(newUTF8("RuntimeVisibleAnnotations"));
		anns.put(out);
		}
	if(ianns != null)
		{
		out.putShort(newUTF8("RuntimeInvisibleAnnotations"));
		ianns.put(out);
		}
	if(attrs != null)
		{
		attrs.put(this, null, 0, -1, -1, out);
		}
	if(invalidFrames)
		{
		ClassWriter cw = new ClassWriter(COMPUTE_FRAMES);
		new ClassReader(out.data).accept(cw, ClassReader.SKIP_FRAMES);
		return cw.toByteArray();
		}
	return out.data;
}

// ------------------------------------------------------------------------
// Utility methods: constant pool management
// ------------------------------------------------------------------------

/**
 * Adds a number or string constant to the constant pool of the class being
 * build. Does nothing if the constant pool already contains a similar item.
 *
 * @param cst the value of the constant to be added to the constant pool.
 *            This parameter must be an {@link Integer}, a {@link Float}, a
 *            {@link Long}, a {@link Double}, a {@link String} or a
 *            {@link Type}.
 * @return a new or already existing constant item with the given value.
 */
Item newConstItem(final Object cst){
	if(cst instanceof Integer)
		{
		int val = ((Integer) cst).intValue();
		return newInteger(val);
		}
	else if(cst instanceof Byte)
		{
		int val = ((Byte) cst).intValue();
		return newInteger(val);
		}
	else if(cst instanceof Character)
		{
		int val = ((Character) cst).charValue();
		return newInteger(val);
		}
	else if(cst instanceof Short)
		{
		int val = ((Short) cst).intValue();
		return newInteger(val);
		}
	else if(cst instanceof Boolean)
		{
		int val = ((Boolean) cst).booleanValue() ? 1 : 0;
		return newInteger(val);
		}
	else if(cst instanceof Float)
		{
		float val = ((Float) cst).floatValue();
		return newFloat(val);
		}
	else if(cst instanceof Long)
		{
		long val = ((Long) cst).longValue();
		return newLong(val);
		}
	else if(cst instanceof Double)
		{
		double val = ((Double) cst).doubleValue();
		return newDouble(val);
		}
	else if(cst instanceof String)
		{
		return newString((String) cst);
		}
	else if(cst instanceof Type)
		{
		Type t = (Type) cst;
		return newClassItem(t.getSort() == Type.OBJECT
		                    ? t.getInternalName()
		                    : t.getDescriptor());
		}
	else
		{
		throw new IllegalArgumentException("value " + cst);
		}
}

/**
 * Adds a number or string constant to the constant pool of the class being
 * build. Does nothing if the constant pool already contains a similar item.
 * <i>This method is intended for {@link Attribute} sub classes, and is
 * normally not needed by class generators or adapters.</i>
 *
 * @param cst the value of the constant to be added to the constant pool.
 *            This parameter must be an {@link Integer}, a {@link Float}, a
 *            {@link Long}, a {@link Double} or a {@link String}.
 * @return the index of a new or already existing constant item with the
 *         given value.
 */
public int newConst(final Object cst){
	return newConstItem(cst).index;
}

/**
 * Adds an UTF8 string to the constant pool of the class being build. Does
 * nothing if the constant pool already contains a similar item. <i>This
 * method is intended for {@link Attribute} sub classes, and is normally not
 * needed by class generators or adapters.</i>
 *
 * @param value the String value.
 * @return the index of a new or already existing UTF8 item.
 */
public int newUTF8(final String value){
	key.set(UTF8, value, null, null);
	Item result = get(key);
	if(result == null)
		{
		pool.putByte(UTF8).putUTF8(value);
		result = new Item(index++, key);
		put(result);
		}
	return result.index;
}

/**
 * Adds a class reference to the constant pool of the class being build.
 * Does nothing if the constant pool already contains a similar item.
 * <i>This method is intended for {@link Attribute} sub classes, and is
 * normally not needed by class generators or adapters.</i>
 *
 * @param value the internal name of the class.
 * @return a new or already existing class reference item.
 */
Item newClassItem(final String value){
	key2.set(CLASS, value, null, null);
	Item result = get(key2);
	if(result == null)
		{
		pool.put12(CLASS, newUTF8(value));
		result = new Item(index++, key2);
		put(result);
		}
	return result;
}

/**
 * Adds a class reference to the constant pool of the class being build.
 * Does nothing if the constant pool already contains a similar item.
 * <i>This method is intended for {@link Attribute} sub classes, and is
 * normally not needed by class generators or adapters.</i>
 *
 * @param value the internal name of the class.
 * @return the index of a new or already existing class reference item.
 */
public int newClass(final String value){
	return newClassItem(value).index;
}

/**
 * Adds a field reference to the constant pool of the class being build.
 * Does nothing if the constant pool already contains a similar item.
 *
 * @param owner the internal name of the field's owner class.
 * @param name  the field's name.
 * @param desc  the field's descriptor.
 * @return a new or already existing field reference item.
 */
Item newFieldItem(final String owner, final String name, final String desc){
	key3.set(FIELD, owner, name, desc);
	Item result = get(key3);
	if(result == null)
		{
		put122(FIELD, newClass(owner), newNameType(name, desc));
		result = new Item(index++, key3);
		put(result);
		}
	return result;
}

/**
 * Adds a field reference to the constant pool of the class being build.
 * Does nothing if the constant pool already contains a similar item.
 * <i>This method is intended for {@link Attribute} sub classes, and is
 * normally not needed by class generators or adapters.</i>
 *
 * @param owner the internal name of the field's owner class.
 * @param name  the field's name.
 * @param desc  the field's descriptor.
 * @return the index of a new or already existing field reference item.
 */
public int newField(final String owner, final String name, final String desc){
	return newFieldItem(owner, name, desc).index;
}

/**
 * Adds a method reference to the constant pool of the class being build.
 * Does nothing if the constant pool already contains a similar item.
 *
 * @param owner the internal name of the method's owner class.
 * @param name  the method's name.
 * @param desc  the method's descriptor.
 * @param itf   <tt>true</tt> if <tt>owner</tt> is an interface.
 * @return a new or already existing method reference item.
 */
Item newMethodItem(
		final String owner,
		final String name,
		final String desc,
		final boolean itf){
	int type = itf ? IMETH : METH;
	key3.set(type, owner, name, desc);
	Item result = get(key3);
	if(result == null)
		{
		put122(type, newClass(owner), newNameType(name, desc));
		result = new Item(index++, key3);
		put(result);
		}
	return result;
}

/**
 * Adds a method reference to the constant pool of the class being build.
 * Does nothing if the constant pool already contains a similar item.
 * <i>This method is intended for {@link Attribute} sub classes, and is
 * normally not needed by class generators or adapters.</i>
 *
 * @param owner the internal name of the method's owner class.
 * @param name  the method's name.
 * @param desc  the method's descriptor.
 * @param itf   <tt>true</tt> if <tt>owner</tt> is an interface.
 * @return the index of a new or already existing method reference item.
 */
public int newMethod(
		final String owner,
		final String name,
		final String desc,
		final boolean itf){
	return newMethodItem(owner, name, desc, itf).index;
}

/**
 * Adds an integer to the constant pool of the class being build. Does
 * nothing if the constant pool already contains a similar item.
 *
 * @param value the int value.
 * @return a new or already existing int item.
 */
Item newInteger(final int value){
	key.set(value);
	Item result = get(key);
	if(result == null)
		{
		pool.putByte(INT).putInt(value);
		result = new Item(index++, key);
		put(result);
		}
	return result;
}

/**
 * Adds a float to the constant pool of the class being build. Does nothing
 * if the constant pool already contains a similar item.
 *
 * @param value the float value.
 * @return a new or already existing float item.
 */
Item newFloat(final float value){
	key.set(value);
	Item result = get(key);
	if(result == null)
		{
		pool.putByte(FLOAT).putInt(key.intVal);
		result = new Item(index++, key);
		put(result);
		}
	return result;
}

/**
 * Adds a long to the constant pool of the class being build. Does nothing
 * if the constant pool already contains a similar item.
 *
 * @param value the long value.
 * @return a new or already existing long item.
 */
Item newLong(final long value){
	key.set(value);
	Item result = get(key);
	if(result == null)
		{
		pool.putByte(LONG).putLong(value);
		result = new Item(index, key);
		put(result);
		index += 2;
		}
	return result;
}

/**
 * Adds a double to the constant pool of the class being build. Does nothing
 * if the constant pool already contains a similar item.
 *
 * @param value the double value.
 * @return a new or already existing double item.
 */
Item newDouble(final double value){
	key.set(value);
	Item result = get(key);
	if(result == null)
		{
		pool.putByte(DOUBLE).putLong(key.longVal);
		result = new Item(index, key);
		put(result);
		index += 2;
		}
	return result;
}

/**
 * Adds a string to the constant pool of the class being build. Does nothing
 * if the constant pool already contains a similar item.
 *
 * @param value the String value.
 * @return a new or already existing string item.
 */
private Item newString(final String value){
	key2.set(STR, value, null, null);
	Item result = get(key2);
	if(result == null)
		{
		pool.put12(STR, newUTF8(value));
		result = new Item(index++, key2);
		put(result);
		}
	return result;
}

/**
 * Adds a name and type to the constant pool of the class being build. Does
 * nothing if the constant pool already contains a similar item. <i>This
 * method is intended for {@link Attribute} sub classes, and is normally not
 * needed by class generators or adapters.</i>
 *
 * @param name a name.
 * @param desc a type descriptor.
 * @return the index of a new or already existing name and type item.
 */
public int newNameType(final String name, final String desc){
	key2.set(NAME_TYPE, name, desc, null);
	Item result = get(key2);
	if(result == null)
		{
		put122(NAME_TYPE, newUTF8(name), newUTF8(desc));
		result = new Item(index++, key2);
		put(result);
		}
	return result.index;
}

/**
 * Adds the given internal name to {@link #typeTable} and returns its index.
 * Does nothing if the type table already contains this internal name.
 *
 * @param type the internal name to be added to the type table.
 * @return the index of this internal name in the type table.
 */
int addType(final String type){
	key.set(TYPE_NORMAL, type, null, null);
	Item result = get(key);
	if(result == null)
		{
		result = addType(key);
		}
	return result.index;
}

/**
 * Adds the given "uninitialized" type to {@link #typeTable} and returns its
 * index. This method is used for UNINITIALIZED types, made of an internal
 * name and a bytecode offset.
 *
 * @param type   the internal name to be added to the type table.
 * @param offset the bytecode offset of the NEW instruction that created
 *               this UNINITIALIZED type value.
 * @return the index of this internal name in the type table.
 */
int addUninitializedType(final String type, final int offset){
	key.type = TYPE_UNINIT;
	key.intVal = offset;
	key.strVal1 = type;
	key.hashCode = 0x7FFFFFFF & (TYPE_UNINIT + type.hashCode() + offset);
	Item result = get(key);
	if(result == null)
		{
		result = addType(key);
		}
	return result.index;
}

/**
 * Adds the given Item to {@link #typeTable}.
 *
 * @param item the value to be added to the type table.
 * @return the added Item, which a new Item instance with the same value as
 *         the given Item.
 */
private Item addType(final Item item){
	++typeCount;
	Item result = new Item(typeCount, key);
	put(result);
	if(typeTable == null)
		{
		typeTable = new Item[16];
		}
	if(typeCount == typeTable.length)
		{
		Item[] newTable = new Item[2 * typeTable.length];
		System.arraycopy(typeTable, 0, newTable, 0, typeTable.length);
		typeTable = newTable;
		}
	typeTable[typeCount] = result;
	return result;
}

/**
 * Returns the index of the common super type of the two given types. This
 * method calls {@link #getCommonSuperClass} and caches the result in the
 * {@link #items} hash table to speedup future calls with the same
 * parameters.
 *
 * @param type1 index of an internal name in {@link #typeTable}.
 * @param type2 index of an internal name in {@link #typeTable}.
 * @return the index of the common super type of the two given types.
 */
int getMergedType(final int type1, final int type2){
	key2.type = TYPE_MERGED;
	key2.longVal = type1 | (((long) type2) << 32);
	key2.hashCode = 0x7FFFFFFF & (TYPE_MERGED + type1 + type2);
	Item result = get(key2);
	if(result == null)
		{
		String t = typeTable[type1].strVal1;
		String u = typeTable[type2].strVal1;
		key2.intVal = addType(getCommonSuperClass(t, u));
		result = new Item((short) 0, key2);
		put(result);
		}
	return result.intVal;
}

/**
 * Returns the common super type of the two given types. The default
 * implementation of this method <i>loads<i> the two given classes and uses
 * the java.lang.Class methods to find the common super class. It can be
 * overriden to compute this common super type in other ways, in particular
 * without actually loading any class, or to take into account the class
 * that is currently being generated by this ClassWriter, which can of
 * course not be loaded since it is under construction.
 *
 * @param type1 the internal name of a class.
 * @param type2 the internal name of another class.
 * @return the internal name of the common super class of the two given
 *         classes.
 */
protected String getCommonSuperClass(final String type1, final String type2){
	Class c, d;
	try
		{
		c = Class.forName(type1.replace('/', '.'));
		d = Class.forName(type2.replace('/', '.'));
		}
	catch(ClassNotFoundException e)
		{
		throw new RuntimeException(e);
		}
	if(c.isAssignableFrom(d))
		{
		return type1;
		}
	if(d.isAssignableFrom(c))
		{
		return type2;
		}
	if(c.isInterface() || d.isInterface())
		{
		return "java/lang/Object";
		}
	else
		{
		do
			{
			c = c.getSuperclass();
			} while(!c.isAssignableFrom(d));
		return c.getName().replace('.', '/');
		}
}

/**
 * Returns the constant pool's hash table item which is equal to the given
 * item.
 *
 * @param key a constant pool item.
 * @return the constant pool's hash table item which is equal to the given
 *         item, or <tt>null</tt> if there is no such item.
 */
private Item get(final Item key){
	Item i = items[key.hashCode % items.length];
	while(i != null && !key.isEqualTo(i))
		{
		i = i.next;
		}
	return i;
}

/**
 * Puts the given item in the constant pool's hash table. The hash table
 * <i>must</i> not already contains this item.
 *
 * @param i the item to be added to the constant pool's hash table.
 */
private void put(final Item i){
	if(index > threshold)
		{
		int ll = items.length;
		int nl = ll * 2 + 1;
		Item[] newItems = new Item[nl];
		for(int l = ll - 1; l >= 0; --l)
			{
			Item j = items[l];
			while(j != null)
				{
				int index = j.hashCode % newItems.length;
				Item k = j.next;
				j.next = newItems[index];
				newItems[index] = j;
				j = k;
				}
			}
		items = newItems;
		threshold = (int) (nl * 0.75);
		}
	int index = i.hashCode % items.length;
	i.next = items[index];
	items[index] = i;
}

/**
 * Puts one byte and two shorts into the constant pool.
 *
 * @param b  a byte.
 * @param s1 a short.
 * @param s2 another short.
 */
private void put122(final int b, final int s1, final int s2){
	pool.put12(b, s1).putShort(s2);
}
}
